Wastewater Flow Management Strategy

Project Highlights

Kerr Wood Leidal (KWL) was retained by the Capital Regional District to develop a Wastewater Flow Management Strategy for its Core Area in Victoria, BC.  A key task was to develop preliminary design flows for proposed treatment plant locations and conveyance facilities under a variety of scenarios.

Developing flows for each option proved challenging because of the sewage system’s complexity.  Considerations included existing and planned pump stations, storage tanks, overflow locations, and I&I reduction plans.  KWL also developed overflow volumes and effluent quality characteristics.

System Assessment

KWL compiled and updated data for the Core Area, and this was used to create the framework for the Wastewater Flow Management Strategy.  KWL derived sanitary per capita loading rates that took into account historical and projected flow reductions resulting from fixture reduction, densification, and water conservation measures.

Program Components

The Wastewater Flow Management Strategy calls for:

• Planning to identify conveyance components for a
  regional wastewater system;
• Complex optimization of multiple conveyance routing
  options; and
• Financial modelling tools and a decision making
  framework.

Results

The strategy provided current design flows for the Capital Regional District’s Core Area, which was subsequently refined by KWL using dynamic computer modelling of overflow locations and information regarding WWTP site selections.